Fig. 1

Experimental design (a) and the procedure of experimental sessions (b). Participants were enrolled in a randomized study consisting of 2 crossover experiments (food-picture and control experiments), and asked to watch a series of pictures for 5 min (visual stimulation session) and to close their eyes for 3 min before and after the picture presentation (eye-closed sessions). Pictures of food items were presented as visual stimuli during the food-picture experiment, and mosaic pictures of food items were presented as visual stimuli during the control experiment. The contents of pictures were not disclosed to the study participants in advance